The White-Rodgers 90-340 Relay is a heavy-duty 2PDT 24V switching relay engineered for reliable performance in fan control centers and general-purpose HVAC applications

the isolated coil 36VDC terminal requires a dedicated ground wire to the coil circuit

which is a vital safety protocol for identifying airflow or combustion issues

Simplifies valve stem packing maintenance by providing a direct-fit replacement for worn mechanical fasteners

using a non-OEM motor can alter the airflow characteristics and increase the full load amps (FLA)

Trane SEN0335 Flow Sensor R-407C The White-Rodgers 90-340 Relay isThe Trane SEN0335 Flow Sensor (OEM Part # SEN00335) is a high precision airflow monitoring component engineered for commercial and residential HVAC systems. Unlike basic mechanical switches that only provide binary on off feedback, this thermal flow sensor utilizes advanced sensor tube technology to provide continuous, real time data on air velocity and volume within the ductwork. This constant feedback loop is essential for HVAC system diagnostics,